An ice rink has a top surface, usually manufactured of concrete or sand, in which hundreds of feet of refrigerant piping or tubing is embedded. When the top surface of the ice rink is applied with water, either initially to form a layer of ice or to resurface the ice of the ice rink, a coolant from the cooling source is circulated through the refrigerant piping or tubing to effect a heat transfer to the water as the water lies on the exposed upper surface of the ice rink, thereby causing the applied water to form into ice.
For a number of years refrigerant piping or tubing has been made from a polymer plastic. When polymer plastic was first introduced, piping with an inner diameter of one inch (2.54 cm) had a wall thickness of approximately 0.125 inches (0.32 cm). In order to increase the efficiency of the heat transfer, experiments were attempted concerning a wall thickness of 0.085 inches (0.22 cm). It was found that this wall thickness was not sufficiently robust enough for refrigeration piping in ice rink applications. The piping or tubing tended to collapse when being covered with concrete and was easily punctured. As a result of such experiments, a minimum wall thickness of 0.100 inches (0.25 cm) was adopted as a standard for piping which had an inner diameter of one inch (2.54 cm). This standard remains recognized in the industry.
It is to be appreciated that if a robust refrigeration piping could be made with a thinner wall thickness, more efficient heat transfer would be obtained from the same.